中文摘要：

将生石灰粉与西藏邦铺矿区中所采取的碎石土混合,分别制成灰土比为3%,5%,7%和9%的改良碎石土,进行大型直接剪切试验,研究石灰改良碎石土的剪切强度特性和改良效果。试验发现:在碎石土中掺入石灰降低了土样的含水率、增大了土样的咬合摩擦和黏聚强度,从而增大碎石土的强度;掺量9%石灰改良碎石土效果最为明显。最后结合室内试验结果与理论公式,采用FLAC3D建立的数值模型分析西藏邦铺矿区北东部剖面碎石土边坡在石灰改良碎石土层、锚杆护坡、抗滑桩护坡及以上方法联合护坡的治理效果。结果表明:石灰改良碎石土层、锚杆加固、抗滑桩联合护坡后,最大水平位移明显变小,没有贯通的塑性区,且有效地减小了下滑力,联合护坡方法较前3种单独采取某种方法时能更有效治理边坡。

英文摘要：

By compounding raw lime powder with gravel-soil taken from mining area in Bangpu of Tibet,the largedirect shear test for improved gravel-soils with lime-soil ratios of 3%,5%,7%and 9%was conducted to investigate the shear strength of gravel-soils with lime improved and the improvement effect. The tests show that:as the moisture content of the soil sample reduces,the bite friction and cohesive strength of samples increases,the shear strength of gravel-soil increase with lime addition;and the improvement effect with lime-soil ration of 9%is best. Finally,based on the indoor test results and theoretical formula,the gravel-soil slope protection with lime improves,anchor slope protection,anti-slide pile slope protection and with the above method combined slope protection in North-east Bangpu of Tibet are analyzed with FLAC3D numerical model. It shows that the maximum horizontal displacement of slope decrease significantly,and with no breakthrough of plastic zone,and the glide force reduce effectively after using the gravel-soil slope joint protection with lime addition,anchor reinforcement and anti-slide pile. The joint slope protection method can be more effective than above three separate method.